COMPUTING Flashcards
CPU stands for
Central Processing Unit
ALU stands for
Arithmetic Logic Unit
CU stands for
Control Unit
The part of the computer that fetches and executes the … stored in the …
Instructions, Main Memory
Explain why having a dual core processor might improve the performance of the computer.
The more cores the computer has the greater number of fetch decode execute cycles it can do simultaneously, this provides vastly superior processing power
How cache size affects the CPU
The cache holds frequently accessed data and instructions, the bigger the cache the less time a processor has to wait for an instruction to be fetched, therefore making a computer faster but if you put too much you wont see any disenable difference as it will take longer to get completely killing its novelty
Out of RAM and ROM which stores data
Both
Out of RAM and ROM which is volatile
RAM
Out of RAM and ROM which is non-volatile
ROM
Out of RAM and ROM which data is read-only
ROM
Out of RAM and ROM which stores currently running data and instructions
RAM
Difference between RAM and flash memory
RAM is volatile, flash memory is not
Discuss whether an optical or solid-state device is the most appropriate media to transfer
these files. You may want to consider the following characteristics in your answer:
● portability
● robustness
● capacity
● cost
Portability
● Both are Small in size / portable and can easily be moved between Kerry’s home and work
● Solid-state can be smaller
● Solid-state less likely to break
Robustness
● Optical are not robust i.e. easily scratched/damaged while being moved
● Solid-state has no moving parts so unlikely to break if dropped
Capacity
● CDs have small capacity
● Depends on Kerry’s files if they are small files e.g. text documents then a CD might be large enough bit if there are lots large files e.g. videos/software then solid state may be more appropriate
Cost:
● Optical cost is small per GB
Solid-state can be reused more times because it’s more durable so may be cost-effective in the long term
Identify three ways that Xander can make use of the file management facility.
He can place his files into folders/directories
He can (re)name files/folders
He can move his files/folders
He can copy/transfer/export files/folders
He can delete his files/folders
He can set permissions/access rights
He can search for files
He can view file details/extensions/file size/type
He can create files/folders
He can sort files/folders // he can put files into a specific order // by
example
He can open files/folders
how the compression software will compress the image file
Use an algorithm
…to remove repeated/unnecessary data
Could use lossy/lossless
lossless will not remove data permanently // lossless means original
file will be restored
lossy is permanent deletion // lossy means original file will not be
restored
Reduce number of pixels // reduce resolution
Record the changes in the colour for each pixel
… instead of the colour
Run length encoding
… record the colour and number of consecutive pixels of that colour
… instead of the colour of every pixel
Decrease colour depth//decrease number of colours
Types of utility system software.
Defragmentation software Encryption software Backup software Anti-virus Firewall Anti-spyware Disk checker/cleaner Auto-update Disk formatting
Why is a smart watch a embedded system
A smart watch is not a general-purpose computer
… which means the smart watch has one/limited/specific/dedicated
function(s)
Smart watch has a microprocessor
… on a single circuit board
It is a computer system that is built within the watch
Runs firmware
Smart watch has built-in OS // difficult to change/manipulate the
OS/function
Smart watch has few components all essential to its purpose
Smart watch has specific hardware required to function i.e.
speaker/headphones
Describe the problems that can arise from unauthorised access to his laptop and
confidential documents.
Malware could be put on the computer
Data protection legislation states personal data must be protected /
breaks Data protection legislation
… breach of privacy
…he could lose his job
Delete files // change data
… so the important work is lost/changed
Steal files/data/information // copy data/files/information // keylogger
transmits data/files/information to third party
… use for illegal activities
… e.g. profit from the data // gain private information // leak
information to the public
Data could be locked
Describe two ways Hamish can help prevent unauthorised access to his laptop.
Password
No access without the password // description of strong password //
limit attempts to guess // changing it regularly
Limited attempts to get into laptop
before laptop is locked
Firewall
Monitor incoming and outgoing transmissions // Stop
unauthorised/unwanted incoming/outgoing transmissions/packets.
Biometrics
Need fingerprint/retina scan
Do not leave laptop logged on/unattended
So that other people cannot physical access it
Physical security // keep in locked room
So that people cannot physically access the laptop
Explain how encryption helps to protect Hamish’s documents
Uses an algorithm to
… jumble/scramble/mix up the data // turns it into cypher text // by
example
If it is accessed it cannot be understood // it is unintelligible
Use of keys to encrypt/decrypt data
Describe the role of the switch in the office network
To connect the devices together
Receives data/packets/traffic
Direct/send data/packets/traffic only to its destination
Creates/generates a list of devices connected to it as it receives
signals
Uses MAC addresses of devices connected to it
Describe how introducing wireless access could have slowed down the network
Wireless transmission is slower than cabled
More devices/users could be connected e.g. mobile phones //
increase in traffic
…reducing bandwidth available for each user // insufficient bandwidth
for users/demand
Wireless can be limited by interference
…such as walls that disrupt the signal // from other wireless
networks/users
Identify two other factors that can affect the performance of a network.
Bandwidth available Number of users (using the network at the same time) (Number of) data collisions Interference // by example e.g. walls Distance data has to travel // signal strength Amount of data being transferred Applications being used Server/CPU performance Using a hub instead of a switch
Explain what is meant by a Virtual Network
a software that separates the normal and the virtual network so people in that network can only access what’s in there network
A private network that runs on a public/existing network
Describe the relationship between the website URL (https://www.ocr.org.uk), the IP address
and the webserver.
The website is hosted on a webserver
The website/webserver has an IP address
(Browser) sends URL to DNS
URL has a linked IP
DNS finds IP
If DNS cannot find the IP it passes request to higher DNS
…if not found return error
IP address sent back to the browser/computer
(Browser) sends request to IP/webserver
Webserver processes request for the website/webpage
…webserver sends the webpage/file/data to the user
Explain why the TCP/IP model uses layers.
A layer can be removed/changed etc.
…without affecting any other layers
Sending an email
from one mail server
to another
SMTP // Simple Mail Transfer Protocol
Transmitting a file
from a client to a
server
FTP // File Transfer Protocol
Viewing a website
using a web browser
HTTP // Hypertext Transfer Protocol
or
HTTPS // Hypertext Transfer Protocol
Secure
Downloading an email
to your computer
IMAP // Internet Message Access
Protocol
or
POP(3) // Post Office Protocol
Fiona is considering selling the game online and not making it available physically in shops.
(a) Describe the environmental impact of Fiona’s decision.
Less/no plastic/paper/raw materials used in manufacture // no need
for packaging // less waste
Less electrical power needed to manufacture
No petrol used to distribute/collect
…smaller carbon footprint
Fewer disks need to be manufactured
Fewer factory emissions // less pollution
Old versions will be thrown away
Fiona releases her game under a proprietary licence.
Explain why a proprietary licence is a more appropriate choice than open source
She can sell it for a fee
Protects/copyrights her source code
…so it can’t be copied/modified/redistributed
